Electronic device chassis and electronic device

Abstract

An electronic device chassis includes a base plate for disposing an electronic device circuit thereon, and a cover for the electronic device circuit housing. The base plate includes a bottom portion and a wall portion. The wall portion includes a screw fastening portion including a contact surface that contacts the cover. The cover includes a screw hole for attaching the base plate. The contact surface of the screw fastening portion is higher than an upper surface other than the contact surface of the wall portion. The upper surface portion covers the side of the housing space facing the base plate. The external side surface cover is provided at a peripheral edge of the upper surface cover portion, and extends toward the base plate so as to be longer than a difference between the contact surface of the screw fastening portion and the upper surface of the wall portion.

What is claimed is: 
     
       1. An electronic device chassis comprising:
 a base plate; and 
 a cover covering the base plate and together with the base plate forming a housing for housing an electronic device circuit, 
 the base plate including
 a bottom portion for disposing the electronic device circuit thereon, and 
 a wall portion extending in an upward direction from a periphery of the bottom portion and forming a side portion of the housing having a sufficient height for surrounding the electronic device circuit, 
 
 the wall portion including:
 an upper surface having contact surfaces and non-contact surfaces, the contact surfaces contacting the cover, and the non-contact surfaces being spaced from the cover and not contacting the cover, 
 one contact surface having a screw fastening portion including a screw hole receiving a screw for fixing the cover to the base plate, 
 the contact surfaces and non-contact surfaces of the wall portion each having a height in the upward direction of the wall portion extending from the bottom portion of the base plate, and the height of the contact surfaces being greater than the height of the non-contact surfaces, 
 differences in the heights between the contact surfaces and the non-contact surfaces providing a gap between the cover and non-contact surfaces of the upper surface of the wall portion as the screw and the screw hole of screw fastening portion fix the cover to the base plate; and 
 
 the cover including:
 an upper portion facing and covering the base plate of the housing, and 
 an external side extending in a downward direction from a peripheral edge of the upper portion and beyond the gap formed between the cover and non-contact surfaces of the upper surface of the wall portion, a downward length of the external side being greater than the differences in heights between the contact surfaces and the non-contact surfaces of the upper surface of the upper wall portion. 
 
 
     
     
       2. An electronic device chassis according to  claim 1 , wherein the external side of the cover is joined to the upper portion of the cover by a bent portion. 
     
     
       3. An electronic device chassis according to  claim 2 , wherein the cover includes a notch at each of four corners thereof. 
     
     
       4. An electronic device chassis according to  claim 1 , wherein the screw hole is offset from a center of the one contact surface toward a center of the housing. 
     
     
       5. An electronic device comprising an electronic device circuit housed in the electronic device chassis according to  claim 1 , wherein
 a substrate of the electronic circuit device is disposed within the housing with a longer dimension of the substrate extending in a longitudinal direction of the housing, 
 one end of the substrate has an input terminal and another end of the substrate has an output terminal, and 
 the wall portion of the housing includes at least one additional screw fastening portion arranged at a position closer to the output terminal than to the input terminal. 
 
     
     
       6. An electronic device comprising:
 an electronic device chassis; and 
 an electronic device circuit disposed in the electronic device chassis; 
 the electronic device chassis comprising: 
 a base plate; and 
 a cover covering the base plate and together with the base plate forming a housing for housing the electronic device circuit, the base plate including
 a bottom portion for disposing the electronic device circuit thereon, and 
 a wall portion extending in an upward direction from a periphery of the bottom portion and forming a side portion of the housing having a sufficient height for surrounding the electronic device circuit, 
 
 the wall portion including:
 an upper surface having contact surfaces and non-contact surfaces, the contact surfaces contacting the cover, and the non-contact surfaces being spaced from the cover and not contacting the cover, 
 one contact surface having a screw fastening portion including a screw hole receiving a screw for fixing the cover to the base plate, 
 the contact surfaces and non-contact surfaces of the wall portion each having a height in the upward direction of the wall portion extending from the bottom portion of the base plate, and the height of the contact surfaces being greater than the height of the non-contact surfaces, 
 differences in the heights between the contact surfaces and the non-contact surfaces providing a gap between the cover and non-contact surfaces of the upper surface of the wall portion as the screw and the screw hole of screw fastening portion fix the cover to the base plate; and 
 
 the cover including:
 an upper portion facing and covering the base plate of the housing space, and 
 an external side extending in a downward direction from a peripheral edge of the upper portion and beyond the gap formed between the cover and non-contact surfaces of the upper surface of the wall portion, a downward length of the external side being greater than the differences in heights between the contact surfaces and the non-contact surfaces of the upper surface of the upper wall portion. 
 
 
     
     
       7. An electronic device chassis according to claim.  1 , further comprising:
 two of the contact surfaces having a screw fastening portion, and 
 the gap between the cover and non-contact surfaces of the upper surface of the wall portion extending between the two contact surfaces having a screw fastening portion. 
 
     
     
       8. An electronic device chassis according to  claim 1 , further comprising:
 the gap between the cover and non-contact surfaces of the upper surface of the wall portion is about 1 mm, and 
 the external side of the cover extends in the downward direction about 5 mm.